It appears you are pulling two homeruns to ckt 12. Is this correct?
Three phases with one neutral is common practice. The neutral only carries the unbalanced current. However, I would not pull ckt 12 in both homeruns on the same neutral.
If the lighting is electronic ballast fluorescents, then we specify a neutral for each circuit due to harmonic currents generated by the switching characteristics of the electronics in the ballast. Our Moderator may have explained harmonics in the technical section. If not, I'm sure he will give us a good explanation.
